design criteria and construction specification
TRANSCRIPT
DESIGN CRITERIA AND CONSTRUCTION SPECIFICATIONS STREETS
VOLUME I
JULY 2015
DEPARTMENT OF PUBLIC WORKS
CITY OF GREELEY, COLORADO
City of
Greele Colorado
FOR WARD
The City of Greeley's Design Criteria and Construction Specification document provides guidance For the design, review, and construction ofthose public improvements in or under the public right-of-way and public easements.
This document assists those in the design, review, and construction industry in providing quality and long-lasting public improvements. The document also provides for consistency in the design, review, and construction areas.
The document is not intended to replace or restrict the design function of the engineer nor the innovativeness and expertise ofdevelopers and contractors. Users of this document are encouraged to submit their ideas and methods of improving the document.
City Engineer
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CITY OF GREELEY, COLORADO
DEPARTMENT OF PUBLIC WORKS
DESIGN CRITERIA AND CONSTRUCTION SPECIFICATIONS
VOLUME 1 STREETS PAGE NO. Street Design Criteria 1-54 Street Construction Specificat ions 55 134 Street Construction Standard Details 135 204 Appendix 205
STREET DES IGN CRITERIA
TABLE OF CONTENTS
SECTION 1- MINIMUM DES IGN CRITERIA
PAGE NO.
1.01 Scope 3 1.02 General 3 1.03 Right-of-Ways and Street Cross-sections 7 1.04 Horizontal A lignment 9 1.05 Street Function, Safety, Accessibility, and Planning Characteristics 11 1.06 Vertical A lignment 13 1.07 Intersections 15 1.08 Cul-De-Sacs 18 1.09 Medians 18 1.10 Sidewalks and Curb Types 19 1.11 Curb Grade and Radius 19 1.12 Drainage 20 1.13 Cross Pans 20 1.14 Inlets 20 1.15 Cross Slope 21 1.16 Pavement Design 21 1.17 Transitions 21 1.18 Street Pro jections into Future Adjoining Subdivisions 21 1.19 Recommended Design Standards for Bus Stops 21 1.20 Street Lighting Standards 22 1.21 Sign Standards 28 1.22 Landscape Standards for Streetscape and Medians 30 1.23 Bike Paths or Trail Crossing Under Roadways 30 1.24 Decelerat ion Lanes and Turning Lanes 30 1.25 Street Markings Standards 31 1.26 Traffic Signal Standards 31 1.27 Transportation Impact Study (TIS) 31 SECTION 2 - SOIL INVES TIGATIONS & PAVEMENT DES IGN 2.01 Soil Investigations 41 2.02 Soils Report 43 2.03 Subsurface Water Investigations 44 2.04 Unsuitable Soils Mitigation 45 2.05 Final Pavement and Design Report 46 2.06 Final Pavement Design So ils Sampling 47 2.07 Final Pavement Design So ils Testing 47 2.08 Pavement Thickness Design Criteria 48 2.09 Pavement Design Procedures 51 2.10 Final Pavement Design Report Certificat ion 53
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LIST OF TABLES
Table 1.03.1 General Parameter 8
Table 1.04.1 Street Flowline Offsets 9
Table 1.04.2 Technical Design Criteria 10
Table 1.06.1 Minimum and Maximum Allowable Street Slope & St reet Grades 13
Table 1.06.2 Minimum Distance for Maximum 2% Approach Grade 14
Table 1.06.3 Minimum Length of Vert ical Curves 14
Table 1.07.1 Sight Distance Triangle Setback 17
Table 1.11.1 Curb Return Radii Criteria 20
Table 1.20.1 Recommended Street Illumination Levels 26
Table 1.20.2 Street Light Requirements 27
Table 1.20.3 Street Lighting Spacing 27
Table 1.20.4 Intersection Light Location 27
Table 1.27.1 Acceptable Level of Serv ice from Intersection Delay 39
Table 2.01.1 Tests Required for Each Boring 43
Table 2.07.1 Expansion Potential o f Subgrade Soil 48
Table 2.08.1 Flexib le Pavement Design Criteria 49
Table 2.08.2 Pavement St rength Coefficients 51
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SECTION 1 MINIMUM DES IGN CRITERIA
1.01 SCOPE
The purpose of this section of this document is to present the City of Greeley criteria for the design of streets. It is to be used by developers, design architects, and design engineers in the design of public and private streets for which approval by the City of Greeley Public Works Department is required. All street design, layout, alignment, and classification shall conform to these design criteria, the City of Greeley Subdivision Regulations, the Greeley Comprehensive Plan, and Chapter 13 and 18 of the Greeley Municipal Code.
1.02 GENERAL
A. MINIMUM S TANDARDS
1. The provisions stipulated in this section are general in nature and shall be considered as applicable to all parts of these specifications, including any supplements and revisions. All construction within the public right-of-way shall be designed by or under the direct supervision of a Professional Engineer (P.E.) registered in the State of Colorado. All drawings and support data submitted to the City for approval must bear their seal and signature. No permits for construction will be issued until these documents have been certified by a P.E. Any over-lot grading completed during the design phase of the project must be certified by a P.E. prio r to issuance of any permits for construction.
2. The design criteria as presented is intended to aid in preparation of p lans and specifications for the
City of Greeley including minimum standards where required. These design criteria are considered min imum and a complete design will usually require more than is presented in this document. As with any design criteria, occasions may arise where the minimum standards are inappropriate. In these cases a variance shall be considered. Written request for each variance should be directed to the City Public Works Department and shall conform to the requirements of the Public Works Director.
3. Whenever the provisions of these Standards are found to be inconsistent with any other
regulations or codes, the Engineer shall determine the standard to apply. The provisions of these regulations are min imum requirements that do not preclude imposition of more restrictive standards by agreement or by law.
4. Projects shall comply with all laws, regulat ions, codes, and ordinances applicable to the design
and the furnishing and performance of the work. Except where otherwise expressly required by applicable laws, regulations, codes or ordinances, the City shall not be responsible for monitoring compliance with any law, regulation, code or ord inance.
5. The City has subdivision regulations and development code that can help define the various
processes required for pro jects.
6. Prior to the contractor beginning work, an approved set of plans and specifications must be on file with the City of Greeley. All contracts, bonds, insurance, permits, and licenses must be fully executed by the Contractor before beginning work.
7. City's review and approval will only be to determine if the plans, specifications, and construction
conform to the City's requirements. City's review and approval will not relieve the Design Professional and Contractor/Owner from responsibility for any variation from the City requirements or adequate design standards. The City's review and approval shall not constitute any assumption of responsibility or liability for the design or construction.
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8. It is the intent and purpose of the standards and specifications to obtain high quality construction throughout, with the completed work complying with the standards and specifications.
9. Reference to standard specifications, manuals, or codes of any technical society, organization, or
association or to the laws or regulations of any governmental authority, whether such reference is specific or by implication, shall mean the latest standard specificat ion, manual, code, or laws or regulations in effect at the time of City acceptance. However, no provision of any referenced standard specification, manual, or code shall be effective to change the duties and responsibilit ies of the City or any of their consultants, agents, or employees from those set forth in these Standards and Specificat ions. Work shall be done in compliance with the accepted plans and to the satisfaction of the City.
10. Consideration shall be given, within the established framework o f local streets, to provide for
uniformity of street widths, proper alignment, street names, and conformity to existing street patterns. The street design shall be d irectly related to the traffic needs. The streets, intersections, driveways, and pedestrian facilities shall be designed to provide for the greatest safety for motorists, pedestrians, and bicyclists.
11. All alleys, when permitted by the Engineer, shall be paved to the full width of right-of-way, or as
approved by the City Engineer, and shall provide paved access to a paved street at both ends.
12. Residential lots adjacent to an arterial street shall be served by a local street. Direct access will not be allowed from any residential lot onto an arterial.
13. Streets of less than the entire min imum right-of-way roadway width should be avoided and
permitted only by approval of the City Engineer. Sufficient engineering data shall be provided to establish feasibility of widening without causing unacceptable drainage, sight distance, or other problems. Street improvement plans shall include the entire width.
14. Development projects and/or subdivisions adjacent to existing public roadways must, in addition
to dedicating additional right-of-way fo r future street expansion needs, evaluate existing improvements along those rights-of-ways. These improvements include but are not limited to public and private utilit ies, storm water facilit ies, irrigation facilities, fences, etc. Developers must provide for proper engineering and construction as necessary to modify and/or protect those facilit ies as well as providing proper development grading along the existing roadways to accommodate the design and construction of the future roadway improvements. Engineer shall include preliminary profiles and cross -sections.
15. All proposed projects shall be referenced to the City of Greeleys adopted control network and
shall obtain the location and elevation of the nearest appropriate reference monument from the Public Works Engineering Div ision prior to survey. If a suitable City of Greeley control monument is not located within two miles of the proposed project, the City will provide one within 20 working days of the request date. The monument name and elevation used shall be clearly marked on all construction drawings.
B. SOILS REPORT AND PAVEMENT DES IGN REPORT
A Soils Report and Pavement Design Report shall be submitted to the City, for review and acceptance, prior to any construction related to the installation of public improvements. The reports shall comply with the requirements outlined in Section II of the St reet Design Criteria part of this manual. A checklist is provided in the Appendix to assist in the preparation of the reports.
C. TRANSPORTATION IMPACT STUDIES
Transportation Impact Studies (TIS) are required in order to adequately assess the impacts of a development proposal on the existing and/or planned street system. Unless waived by the City
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Engineer, a TIS report shall be required for all development proposals. The TIS shall be prepared by a Professional Engineer.
D. PRECONS TRUCTION CONFERENCE
A preconstruction conference may be required prior to the issuance of any permits for construction. Attendance should include representatives from the Public Works Department, Development Coordinator, Developer/Owner, Design Engineer, General Contractor, and Sub-contractors including; earthwork, utilit ies, curb and gutter, paving, and signing.
E. DEFINITIONS AND ABBREVIATIONS
Wherever the following words, phrases, or abbreviations appear in these specificat ions they shall have the following meanings.
1. AASHTO American Association of State Highway and Transportation Officials.
2. ADA Americans with Disabilities Act.
3. ADT Average Daily Traffic Count.
4. ASTM American Society for Testing Materials.
5. CITY An individual employed by the City of Greeley whom is authorized to make the
applicable decisions on behalf of the City.
6. CITY ENGINEER a term used in situations where a decision or action may be required by the City Engineer or h is authorized representative employed by the City of Greeley. The Engineer shall have the authority on behalf of the City to ascertain that all design and construction is equal to or exceeds the min imum requirements set forth in these criteria and standards.
7. CDOT Colorado Department of Transportation.
8. CONSTRUCTION DRAWINGS detailed and working drawings including plan, profile, and
detail sheets of proposed utility drainage and street improvements approved by the Engineer.
9. CONSULTANT the partnership, corporation, or individual who is registered as a professional engineer, according to Colorado statutes, and who is hired by the Developer/ Owner, and is empowered to act as his agent for the project.
10. DESIGN ENGINEER the partnership, corporation, or individual who is registered as a professional engineer, according to Colorado statutes, and who is hired by the Developer/Owner, and is empowered to act as his agent for the project. The Design Engineer may also be referred to as the Professional Engineer, Civil Engineer, Geotechnical Engineer, or Traffic Engineer.
11. DESIGN SPEED a speed determined for design and correlation of the physical features of a street that influence vehicle operation; the maximum safe speed maintainable on a specified section of street when conditions permit design features to govern. Design speed is generally higher than the posted speed limit in o rder to provide a factor o f safety and consider other conditions or uses of the street that may affect vehicle operation.
12. DEVELOPER the owner, corporation, association, partnership, or individual who has entered into an agreement with the City and has entered into an agreement with the Contractor to perform the construction work.
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13. DRIVEWAY APPROACH that portion of concrete extending from the street gutter lip to the property line or back of sidewalk, or the full width of the access from the public right-of-way to private property.
14. EYEBROW a bulb or semi-circular extension of a curb on one side of a street or at an elbow intersection.
15. GEOTECHNICAL ENGINEER the partnership, corporation , or indiv idual who is registered as a Professional Engineer or Professional Geologist, according to Colorado Statutes, and who is hired by the Developer/Owner to prepare the Soils Report and Final Pavement Design Report for the project.
16. MAY a permissive condition. No requirement for design or application is intended.
17. MGPEC Metropolitan Government Pavement Engineers Council.
18. MUTCD Manual of Unifo rm Traffic Control Devices
19. OWNER the developer, corporation, association, partnership, or individual who has entered into an agreement with the City and has entered into an agreement with the Contractor to perform the work.
20. PLANS detailed and working drawings including plan, profile, and detail sheets of proposed utility improvements, approved by the City Engineer.
21. PROFESSIONAL ENGINEER an individual whom has been licensed and has active status as determined by the Colorado Department of Regulatory Agencies, State Board of Registration for Professional Engineers.
22. ROAD OR STREET as used in this specification shall include the pavement section, right-of-way, sidewalks, driveways, bikeways, alleys, and alley approaches.
23. SHALL a mandatory condition. Where certain requirements in the design of application are described with the "shall" stipulation, it is mandatory that these requirements be met.
24. SHOULD an advisory condition. Where the work "should" is used, it is considered to be advisable usage, but not mandatory. Deviat ions may be allowed when reasons are given which show that the intent of the standard is met.
25. STANDARD STREET SPECIFICATIONS the current City of Greeley Design Criteria and Construction Specifications for St reets.
26. STOPPING SIGHT DISTANCE shall mean that distance measured from the drivers eye, 3.5 feet above the pavement to the top of any object six inches high on the pavement anywhere on the road.
27. STREET WIDTH that distance measured from curb face to curb face across a street which should generally include the gutter pans on each side.
28. UTILITIES shall mean all utilit ies on site prior to the time of any design; such as but not limited to water lines, sanitary sewer lines, drainage lines, electric lines, gas lines, telephone lines, and cable television lines.
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1.03 RIGHT-OF-WAYS AND S TREET CROSS-S ECTIONS
A. GENERAL
1. Sufficient right-of-way shall be provided as required for the traffic needs and cross-section and maintenance of the street including cut or fill slopes, auxiliary lanes, landscaping, signing, utilit ies, and other aspects of the development.
2. Standard right-of-way and street widths shall meet or exceed the minimums set forth in the Design
Criteria. Additional right-of-way and roadway width may be required to accommodate traffic or other development needs such as turn lanes, deceleration lanes, extra lanes, pedestrian or bicycle facilit ies, landscaping, utilit ies, or construction requirements such as cut or fill slopes.
B. DES IGN CRITERIA
1. See Table 1.03.1 General Parameters. Standard right-of-way and street widths shall meet or
exceed the following min imum criteria.
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Table 1.03.1 General Parameters
Street Classification
Park way Arterial Multi-modal
4-6 Lanes
Major Arterial 4 Lanes
Minor Arterial 4-Lanes
Major Collector 4-Lanes
Minor Collector
2 Lane
Local Commercial/ Industrial
2 Lane
Local Residential
Local Low-volume
Right-of-Way Width 140'/165 125'/135 110' 100' 75' 50' 60' 50'
Roadway Width* 94' 78 78' 73' 50' 37' 34' 24'
Width at Intersections* 130' 102' 78' 73' 45' 37' 34' 24'
Number of Travel Lanes 4-6 4 4 4 2 2 2 2
Travel Lane Width 12' 12' 12' 11' 11' 11' 10' 10'
Designated Bike Lanes Y Y Y Y Y N N N
Bike Lane Width 10'*** 6' 6' 6' 6' 0 0 0
Parking Lane Width None None None None 8 None 7' None
Traffic Volume ADT 35,000 20,000 15,000 10,000 3,500 5,000 1,500 500
Design Speed MPH 65 60 55 45 40 35 35 35
Posted Speed MPH 55 50 45 40 35 30 30 30
Continuity 5 Miles 5 Miles 3 Miles 3 Miles 1 Mile 1 Mile 1 Mile 1 Mile
Turn Lanes ** Required Required Required Required Required Required NO NO
*Flow Line to Flow Line **Left-turn lanes are always required, right-turn lanes are required if TIS ind icates need. ***Detached Bikeway in lieu of on-street Bike Lane See standard details for performance options.
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1.04 HORIZONTAL ALIGNMENT
A. GENERAL
1. Horizontal alignment shall provide for the safety of motorists, pedestrians, and bicyclists.
2. The street pattern in a subdivision shall be the most advantageous configuration to serve adjoining areas and the entire neighborhood or district. Where appropriate to the design, proposed streets shall be continuous and in alignment with existing, planned, or platted streets.
3. Proposed streets shall be extended to the boundary lines of the subdivision, except where
prohibited by topography or other physical conditions, or where such extension is not necessary for connection to adjacent properties. Where streets will be extended beyond the property line, sufficient engineering data shall be provided to establish feasibility of extension meet ing City standards.
4. Streets shall be placed in accordance with the City of Greeley Comprehensive Transportation
Master Plan where applicable.
5. Utility easements shall be provided as required by utilities for all street classificat ions.
B. DES IGN CRITERIA
1. All proposed streets shall intersect at right angles unless topography and other limiting factors of good design and safety require otherwise.
2. Where streets intersect with other streets are not in alignment, the street's centerline shall be offset
in accordance with the fo llowing table:
Table 1.04.1 Street Flowline Offsets
INTERSECTING
ROADWAY MINIMUM
OFFSET Arterial 660 feet
Collector 330 feet Local 135 feet
3. Flowline offset distances shall be measured from nearest flowline to nearest flowline.
4. The number of intersecting streets along Arterials and Collectors shall be held to a min imum. The allowable spacing of intersections varies depending on signalization and presence of a raised center median. Refer to access management section of Technical Design Criteria Table 1.04.2.
5. Local streets should not intersect Major Collectors or Arterial streets.
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Table 1.04.2
Technical Design Criteria
Design Element Arterial Collector Local
Park way
4 or 6 Lane
Major 4 Lane
Minor 4 Lane
Major 4 Lane
Minor 2 Lane
Commercial/Industrial Residential
Low Volume
Overall Design Parameters Design Speed/ Posted Speed
65 MPH 50-55
60 MPH 45-50
55 MPH 45-30
45 MPH 40-30
40 MPH 35-30
35 MPH 30
35 MPH 30
35 MPH 30
Stopping Sight Distance 645' 570' 495' 360' 305' 250' 250' 250' Horizontal Alignment Minimum Centerline radius 1660' 1530' 1200' 745' 450' 371' 250' 200' Maximum Super-elevation 6% 5% 5% 4% NA NA NA NA Minimum Tangent between curves or at i i
400' 300' 300' 250' 150' 150' 100' 50' Vertical Alignment Maximum Centerline Grade 5% 5% 5% 5% 5% 5% 5% 8% Minimum Gutter Flow line Grades 0.4% 0.4% 0.4% 0.4% 0.4% 0.4% 0.4% 0.4% Intersection Design Minimum sight distance at driveways & intersections* 720' 665' 610' 500' 445' 390' 390' 390'
Access Management (1) (2) (1) (2) (1) (2) (1) (2)
Minimum distance between Intersections
Signalized 2640' 2640' 1320' 1320' NA NA NA NA
Un-signalized NA 1320 NA 1320 1320 ** 425' 660' 330' 330' 135 135 135
Minimum distance between driveways NA *** 590 NA *** 350' 660'
*** 300' 660'
*** 250' 200' 135' 10' see S-24 NA
Driveway Configuration Radial curb return Radial curb return
Radial curb return
Radial curb return
Curb Cut or Rad ial
Curb Cut or Radial Curb Cut Curb Cut
* Left-turn from Stop Sign (1) Without Raised Median ** Movement Only Per Approval of Traffic Engineer (2) With Raised Median *** Right-in / Right-out Only Per Approval of Traffic Engineer Note: Deviations require a t raffic study and analysis by a licensed engineer and must be approved by the City Traffic Engineer.
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1.05 STREET FUNCTION, SAFETY, ACCESS IBILITY AND PLANNING CHARACTERIS TICS
A. GENERAL
All street classificat ions shall be designed for the safety of motorists, pedestrians and bicyclists. Accessibility shall be provided in accordance with all ADA (Americans With Disabilities Act) requirements. Alleys are not mentioned in these criteria because of the large amount of variables in their design. However, any permanent alley design must be approved by the City.
B. DES IGN CRITERIA
1.
LOCAL Low Volume
FUNCTION Local streets serve local traffic and have low traffic volumes. Traffic carried by Local streets should have an origin or a destination within the neighborhood, and are designed to discourage through traffic. Local streets are typically designed to connect to Collector streets, although they can also be designed as cul-de-sacs or to provide connectivity to adjacent subdivisions.
CHARACTERISTICS Local Low Volume streets shall be for residential developments with a minimum lot size of two (2.0) acres (gross). Local streets should not intersect Major Collectors or Arterial streets. Traffic control shall be provided using stop signs at all intersections.
2.
LOCAL Residential
FUNCTION Local streets shall provide local traffic and have low traffic volumes. Traffic carried by Local streets should have an origin or a destination within the neighborhood, and are designed to discourage through traffic. Local streets are typically designed to connect to Collector streets, although they can also be designed as cul-de-sacs or provide connectivity to adjacent subdivisions.
CHARACTERISTICS Local residential streets are intended for use in medium to high density residential neighborhoods. Local streets should not intersect Major Collectors or Arterial streets. Parking shall be allowed on both sides of local residential streets. Traffic control shall be provided using stop signs at all intersections.
3.
LOCAL Commercial/Industrial
FUNCTION Local streets serve local traffic and have low traffic volumes. Traffic carried by Local streets should have an origin or a destination within the neighborhood, and are designed to discourage through traffic. Local streets are typically designed to connect to Collector streets, although they can also be designed as cul-de-sacs or to provide connectivity to adjacent subdivisions.
CHARACTERISTICS Local Commercial/Industrial streets are intended for commercial/industrial developments. These streets may intersect Major Collectors in some situations, but should not intersect with an Arterial Street. On-street parking, backing, or loading maneuvers shall not be allowed. Traffic control shall be provided using stop signs at all intersections.
4.
MINOR COLLECTOR
FUNCTION Minor Collectors collect and distribute traffic between Arterials, Major Collectors, and Local streets and serve as main connectors within communit ies, linking one neighborhood with another.
PLANNING CHARACTERISTICS Minor Collectors are generally intended for use within residential neighborhoods or to connect smaller neighborhoods. Intersections with other Collector
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and Arterial streets should be at least one-quarter (1/4) mile apart. Regulation of traffic shall be accomplished through the use of stop signs and channeling.
a.
MAJOR COLLECTOR
FUNCTION Major Collector streets shall be designed to permit relat ively unimpeded traffic movement and are intended for use on those routes where four (4) moving lanes are required but where a larger classified street is not warranted.
PLANNING CHARACTERISTICS Major Collector streets should be employed where t raffic demands dictate. Major Collector streets are intended for use in commercial/ industrial areas or high density residential. See the Street Standards Technical Design Criteria Chart for allowable intersection spacing. Street parking is not allowed on Major Collector streets. Access from streets of lower classification will be permitted, but in all cases will be controlled by traffic control devices. Direct access to abutting property is not permitted unless no other access is reasonably available. Regulation of t raffic shall be accomplished through the use of traffic signs, signals, and channeling. Traffic signals will normally be located only at intersections with Arterial Streets.
b.
MINOR ARTERIAL
FUNCTION Minor Arterial streets permit relatively unimpeded traffic movement and are intended for use on those routes where four moving lanes and one left-turn lane are required but where a Major Arterial cross section would not be warranted.
PLANNING CHARACTERISTICS Minor Arterials should be employed where traffic demand dictates. Minor Arterials should be spaced approximately one (1) mile apart and should, where possible, be continuous. Minor Arterial should act as boundaries between neighborhood areas. Intersections with Collectors streets should be at least one-quarter (1/4) mile apart. See the Street Standard Technical Design Criteria Chart for allowable intersection spacing. No street parking is allowed on Minor Arterial streets. Regulation of traffic shall be accomplished through the use of traffic signs, signals, and channeling. Traffic signals will normally be required at intersections. Access from streets of lower classification will be permitted, but in all cases will be controlled by traffic control devices. Direct access to abutting property is not permitted unless no other access is reasonably available. Minor Arterial streets are intended to have continuous medians.
7.
MAJOR ARTERIAL
FUNCTION Major arterial routes permit rap id and relat ively unimpeded traffic movement throughout the City, connecting major land use elements as well as connecting to outside communit ies.
PLANNING CHARACTERISTICS Major Arterial streets should not bisect neighborhoods but should act as boundaries between them. Major Arterial should be spaced approximately one (1) mile apart. See Street Standards Technical Criteria Chart for intersection spacing criteria. Local streets should not intersect with Major Arterial. Street parking is not allowed on Major Arterial. Regulation of Traffic shall be accomplished through the use of traffic signals and channeling. Major Arterial streets are intended to have continuous medians.
8.
PARKWAY ARTERIAL
FUNCTION Parkway Arterial routes provide the same function as Major Arterial streets, with the allowance fo r higher speeds, additional lane potential, h igher volumes, and provisions for multi-modal enhancement. PLANNING CHARACTERISTICS Parkway Arterial streets should act as boundaries between neighborhoods, and should be spaced greater than one (1) mile apart. They provide for major multi-modal opportunities along major t ransportation corridors.
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1.06 VERTICAL ALIGNMENT
A. GENERAL
Vertical alignment and grades shall be designed to bear a logical relationship to the existing topography, drainage needs and shall provide for the safety of motorists, pedestrians, and bicyclists.
B. DES IGN CRITERIA
1. All proposed streets shall conform to the minimum and maximum allowable street slope and street
grade standards shown in the following table:
Table 1.06.1 Minimum and Maximum Allowable Street Slope and Street Grade
Street Type Street Grades %Min. / Max. Cross Slope %
Parkway Arterial (a) 0.4/5.0 2.0 Normal crown (b) 6.0 Max for super-elevation.
Major Arterial (a) 0.4/5.0 2.0 Normal crown (b) 5.0 Max for super-elevation.
Minor Arterial (a) 0.4/5.0 2.0 Normal crown (b) 5.0 Max for super-elevation.
Major Collector (a) 0.4/5.0 2.0 Normal crown (b) 4.0 Max for super-elevation. Minor Collector (a) 0.4/5.0 2.0 Normal crown (b)
Local-Com. / Ind. (a) 0.4/5.0 2.0 Normal crown (b)
Local-Residential (a) 0.4/5.0 2.0 Normal crown (b) Local-Low (a) Volume 0.4/5.0 2.0 Normal crown (b)
Alley (where permitted) 0.4/5.0 2.0 Min.
Emergency 0.4/5.0 2.0 Min.
Notes: a. Grading behind sidewalks and between detached sidewalk and curb shall
be a maximum of 4:1. Special conditions outside of this range may be approved by the City Engineer.
b. Normal crown slope is 2 percent. One percent to 5 percent is allowable at transition and other non-normal sections with special design review. Special conditions outside of these ranges may be approved by the City Engineer.
2. Minimum grade on gutter shall be 0.4 percent. Part icular attention shall be g iven to maintain a 0.4
percent minimum grade especially on a sag vertical curve. Crosspans, cul-de-sacs, eyebrow, and curb return gutters shall have a min imum grade of 0.6 percent.
3. Connections with existing streets shall be made in a way that will create a s mooth transition. The
higher volume street at an intersection shall govern the through grade and cross-sections. The maximum allowable approach grade at an intersection shall be two (2%) percent for a distance as designated by the following table:
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Table 1.06.2
Minimum Distance for Maximum 2% Approach Grade
Approaching street Local Collector Arterial
Local 30 Feet 50 Feet 75 Feet
Collector 75 Feet 150 Feet
Arterial 200 Feet
Distances shown are measured from the flowline intersections.
The intersection of any street with a Major street shall be designed to the ultimate street grade of the Major street. The grading of the property adjacent to the Major street shall meet these ultimate grades. A detail of the intersection sufficient to show drainage and grades must be provided.
Connection with existing streets shall be smooth transitions and existing grades shall be shown for at least one hundred and fifty (150') feet on all sides of the connection. The grade and ground lines of all streets that dead end, except cul-de-sacs, shall be continued for five hundred (500') feet beyond the proposed construction. The grade and ground lines of all Arterial Streets shall be designed to continue one-thousand (1000') feet beyond the end of proposed construction.
4. Vertical curves shall meet or exceed the following minimum criteria:
Table 1.06.3
MINIMUM LENGTH OF VERTICAL CURVES (IN FEET)
Grade Change % Arterial Collector Other
0.00 - 0.99 none none none
1.00 - 1.99 200 120 60
2.00 - 2.99 300 160 90
3.00 - 3.99 450 220 120
4.00 - 4.99 600 280 150
5.00 - 5.99 700 330 180
6.00 - 6.99 --- 380 210
7.00 - 7.99 --- 430 240
8.00 - 8.99 --- --- 270
9.00 - 9.99 --- --- 300
10.00 - 10.99 --- --- 330
11.00 - 12.00 ---- ---- 360
Note: Lengths above do not allow passing on crest of vertical curves. Design
may warrant a passing move on Collectors or Arterial, which would lengthen the vertical curves. The required lengths for passing will be provided on a case-by-case basis by the Engineer.
Profile may be designed with a maximum one percent (1%) change in grade at the vertical point of intersection (VPI).
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5. The purpose of super elevating a roadway is to improve the riding comfort on curves where the
traveling speed is great enough to exert a lateral thrust greater than that which can reasonably be resisted by frict ion alone.
In the City of Greeley, super elevation may be allowed on Arterial streets and selected Collector streets in order to reduce the minimum centerline rad ius allowed. Super-elevation shall not be used on Local streets. When super-elevations are required, the super elevation shall be in accordance with the recommendations of AASHTO and approved by the City Engineer.
When super elevation is used, a min imum one hundred (100') foot run-out shall be used entering and exiting the super-elevated portion. In cases where the super elevation transition changes the gutter on one side of the street from water carrying to non-water carrying, the water must enter a storm sewer system or other acceptable outlet from the street rather than crossing said street in sheet flow. The gutter shall always be inflow type.
When super-elevation is used, the rate of super-elevation shall be clearly shown on the drawings along with exaggerated (preferably 1"= 20' Horizontal, 1"= 1' Vertical) profiles of the centerline and both flowlines. The super-elevation run-out length, crown run-out length, and point at which full super-elevation is reached shall be clearly shown.
6. The design engineer shall show either centerline profile or both flowline profiles. If centerline
profiles are provided, the flowline profile informat ion, distances and grades, shall also be provided everywhere it is not parallel to the centerline and along all horizontal curves. If flowline profiles are provided, the design engineer shall also show centerline profiles through intersections and details at any mid-block crosspans to provide smooth riding transitions. The actual distance and grades of curb returns shall be given for all intersections. Flowline profiles shall be shown around cul-de-sacs, kneecaps, bulb-outs and elbows.
For arterial and major collector streets and for widening of existing streets, the design engineer shall provide cross-sections to the construction limits at fifty (50') foot intervals on all streets showing existing and proposed construction. Cross-section profiles shall be p rovided to include the street, curb, gutter and walk to a point twenty (20') feet beyond walk.
1.07 INTERS ECTIONS
A. GENERAL
1. Intersections shall be designed to provide for the safety of motorists, pedestrians, and bicyclists.
2. At street intersections, property lines shall be truncated as shown in Standard Detail S-9 to provide adequate right-of-way for curb ramps and utilit ies.
3. Intersection design shall take into consideration auxiliary turn lanes as required by the approved
Transportation Impact Study, or as required for site specific conditions.
B. DES IGN CRITERIA
1. The design criteria for all street intersections shall conform to the Horizontal Alignment Design
Criteria outlined in Sect ion 1.04 above. All intersections shall be designed and constructed with pedestrian curb ramp access on all corners in accordance with all ADA requirements. See Standard Details.
2. Intersection Obstruction Free Areas Intersection obstruction-free area shall mean that area
which the City shall be required to maintain in order to preserve the sight, distance, and safety of motorists, pedestrians, and bicyclists, by requiring an unobstructed intersection sight distance
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(ISD) area. ISD is the unobstructed line of sight necessary for most drivers stopped at an intersection to see an approaching vehicle to avoid a collision. When the lines of sight for both left and right directions are combined, a sight triangle is formed. There should be no visual obstructions.
The ISD depends on the street operating speed and desired maneuver of existing vehicle. These areas shall be free from shrubs, ground covers, berms, fences, signs, structures, parked vehicles, or other materials. Trees, within the sight distance triangle (whether with in the public right-of-way or on private property) must not impair sight distance. Permits for p lanting trees are required by the City Forestry Division which will provide guidelines for the type, location, and spacing of trees.
These distances are typical sight distance triangles to be used under normal conditions and may be modified by the City in order to protect the public safety and welfare in the event that exceptional sight conditions necessitate such a modification.
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1.08 CUL-DE-S ACS
A. GENERAL
Permanent no outlet streets shall be in the fo rm of a cul-de-sac. Such cul-de-sacs are allowed on local streets only. No outlet streets without a cul-de-sac shall not be allowed unless designed to connect with a future street. If the temporary no outlet street is longer than eight hundred (800') feet, or serves as primary access to any lot, a temporary turn-around or a temporary paved connection to another street shall be provided. At least an eighty (80') foot temporary turn-around easement shall be provided when needed on temporary dead-end streets. Such turn-around easement shall not be required if no lots in the subdivision are dependent on such street for access.
B. DES IGN CRITERIA
1. Permanent no outlet streets in the form of a cu l-de-sac shall have a maximum length of 500 feet
(measured along the centerline, from the centerline of the intersecting street to the center point of the bulb), or a maximum of ten (10) lots on a Local low-volume street or twenty-five (25) lots on a Local Residential street. The right-of-way for a cul-de-sac shall conform to the right-of-way requirements for the specific street classificat ion of the cul-de-sac.
2. Cul-de-sacs on a Local low-volume street shall have a min imum pavement radius of fo rty (40')
feet if no truck traffic is anticipated. Cul-de-sacs on Local streets shall have a min imum pavement radius of fifty (50') feet if t ruck traffic is anticipated, or if a fire hydrant is located within the cul-de-sac. See Standard Detail S-10.
3. Surface drainage on a cul-de-sac shall be toward the intersecting street, or if that is not possible, a
drainage outlet and right-of-way shall be provided from the cul-de-sac. 1.09 MEDIANS
A. GENERAL
Prior to design of any medians on public streets, the Standard Details shall be checked and City staff consulted for specific requirements; such as median width, landscaping, decorative concrete, median cover design, etc. Generally, medians should be designed to meet the requirements of the AASHTO "Policy on Geometric Design of Highways and Streets" (latest revision).
B. DES IGN CRITERIA 1. The design of medians shall include the evaluation for needed turn lanes and accesses. This need
will be determined by a Traffic Impact Study and current AASHTO requirements.
2. Landscaped medians shall be provided with drainage facilities to handle sprinkler runoff and nuisance flows. When low maintenance landscaping is used in conjunction with trickle irrigation, outfall curb and gutter should be used; otherwise, inflow curb and gutter with a properly designed storm drain system shall be installed.
3. The nose of the median on arterial streets should be a minimum of twenty (20') feet behind the
flowline of the intersected street and shall not encroach on pedestrian crosswalks. Turning templates must be used to determine the shape of the median.
4. The min imum radius for nose curbs should be two (2') feet to flowline. The min imum width of a
median shall be four (4') feet.
5. Medians shall be irrigated and landscaped whenever possible. The minimum width of landscaped medians shall be twelve (12') feet.
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1.10 SIDEWALKS AND CURB TYPES
A. GENERAL
1. Sidewalks shall be designed to provide for the safety of pedestrians.
2. All intersections shall be designed and constructed with pedestrian curb ramp access on all co rners in accordance with all ADA requirements.
3. Meandering sidewalks shall be subject to special review and approval by the City.
4. The min imum sidewalk width shall be five (5') feet. Wider sidewalks may be required by the City
where warranted by anticipated pedestrian traffic; such as at or near schools and/or parks.
B. DES IGN CRITERIA
1. Local-Low Volume
Intersections shall be designed at grade with direct access to abutting property permitted. A two (2') foot wide concrete shoulder shall be provided on each side of the street. Curb and gutter and sidewalks are normally not required on Local-Low Volume streets.
2. Local-Residential
The standard curb and gutter for Local Residential streets is the vertical face curb with sidewalk detached.
3. Local-Commercial/Industrial
The standard curb and gutter for Local Commercial/Industrial streets is vertical face curb and gutter. Sidewalks shall be detached.
4. Minor Collector and Major Collector
The standard curb and gutter is vertical face curb and gutter. Sidewalks shall be detached, and the detached area shall have a minimum width of at least six (6) feet wide.
5. Minor Arterial and Major Arterial
The standard curb and gutter for Arterial streets is vertical face curb and gutter. Six (6) foot on-street bike lanes shall be provided. Sidewalks shall be detached.
1.11 CURB GRADE AND RADIUS
A. GENERAL
1. Intersections and approved pedestrian crossings shall be designed and constructed with pedestrian curb ramp access in accordance with ADA requirements.
2. Drive approaches shall be constructed in accordance with the Standard Details. Any deviation
from these details shall be considered on an individual basis.
3. Minimum grade on gutter shall be 0.4 percent. Part icular attention shall be g iven to maintain a 0.4 percent minimum grade especially on a sag vertical curve.
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B. DES IGN CRITERIA
TABLE 1.11.1 Curb Types and Curb Return Radii Criteria
STREET CLASS STANDARD CURB TYPE
CURB DETAIL
RETURN RADII
INTERSECTING STREET
Arterials Vertical S-16 50-60 30-40 Arterials Collectors
Collectors Vertical S-16 30-40 20-30 20-30
Collectors Locals Driveways
Locals Major & Commercial/Industrial Residential Local Low Volume
Vertical Vertical Shoulder
S-16 S-16 S-1
20-30 20 40
Locals, Driveways and Alleys
1.12 DRAINAGE
Drainage system design shall be in accordance with current Storm Drainage Design Criteria adopted by the City of Greeley.
1.13 CROSS PANS
A. GENERAL
Cross pans shall be designed and constructed in accordance with the Structural Design Criteria and Standard Details section of this manual.
B. DES IGN CRITERIA
1. Cross pans shall be a min imum of eight (8') feet wide, 8" thick concrete, with a maximum depth of one (1") inch. Mid-block cross pans shall be a minimum of ten (10') feet wide with one and one-quarter (1-1/4") inches maximum depth. Larger widths may be required by the City.
2. Cross pans are discouraged on Arterial o r Major Collector streets or at signalized intersections.
3. Minimum grade on cross pans at flowline of pan shall be 0.6 percent.
4. Cross pan approaches shall be designed using the appropriate design speeds.
5. Cross pan approaches on Local streets at intersections shall be in accordance with Standard
Details.
1.14 INLETS
A. GENERAL 1. Inlets shall not be installed in the curb return and shall not be in line with accessibility ramps. In
residential developments inlets should be located at property lines where possible.
2. Inlets shall be designed and constructed in accordance with Storm Drainage Design Criteria adopted by the City of Greeley.
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3. Inlet structures shall not be constructed until the curb and gutter has been installed, unless approved by the City Engineer.
1.15 CROSS SLOPE
A. GENERAL
See Section 1.06 Vertical Alignment.
B. DES IGN CRITERIA
1. A normal cross slope on all streets shall be 2.0 percent as measured from the lip of gutter to the street centerline.
2. On streets with raised medians, normal cross slope 2.0 percent shall be measured from lip of
median gutter to lip of gutter at street edge.
3. Maximum allowable cross slope shall be 5.0 percent on all new construction.
4. Cross slope for widening an existing street or for adding turn lanes should be a straight-line grade from crown to lip of new gutter adjacent to new pavement.
5. Cross Slopes other than 2% shall be indicated on plans and approved by the City Engineer.
1.16 PAVEMENT DES IGN
Pavement design shall be in accordance with Section 2 So ils Investigation and Pavement Design of this manual.
1.17 TRANSITIONS
Lane and pavement transition length shall be in accordance with the latest AASHTO requirements.
1.18 STREET PROJECTIONS INTO FUTURE ADJOINING S UBDIVIS IONS
A. GENERAL
1. The location of projected streets shall allow for the proper extension of the storm drains, sanitary sewer system, water lines, and non-potable water lines where applicable.
2. No-Outlet Street: Where a street is indicated to end into an adjacent unplatted area, the developer
shall provide written approval from the adjacent landowner to discharge storm drainage from the street onto the adjacent land, and verification that the storm drainage will be properly detained.
3. No-Outlet Streets shall end at the property line with a temporary cul-de-sac unless the City
Engineer approves otherwise.
4. All stub streets shall be constructed as a part of the development project. Type III barricades shall be installed on all stub streets that do not end on a cul-de-sac.
1.19 RECOMMENDED DES IGN S TANDARDS FOR BUS STOPS
A. GENERAL
The following min imum design standards are offered as guidelines for the design and construction of bus stops. The City may vary any of the fo llowing requirements as deemed appropriate for the site and its particular situation. It is important that the applicant contact the City early in the review process to determine the exact location and proposed capacity of a bus stop in the proposed development.
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B. DES IGN S TANDARDS
1. Bus Lane Width
Bus lanes and stops should be asphalt or concrete and at least ten (10') feet wide.
2. Bus Stop Lengths
:
Near-side bus stops should be concrete and at least fifty (50') feet long for a single bus, plus a thirty (30 ') to seventy (70 ') foot distance to the radius of intersection.
Far-side bus stops should be concrete and provide a fifty (50') feet loading area p lus a thirty (30 ') to seventy (70 ') feet distance to the radius of intersection.
Mid-block bus stops shall be paved and include transition requirements for near and far-side bus bays. Total impacted area for a single bus stop would be seventy feet (70') with a thirty feet (30 ') bus stop and two twenty feet (20 ') transitions before and after the bus stop.
All bus stop locations should be approved by the City Transit Manager.
3. Bus Shelters
Shelters should be used at major bus stops to protect users from the weather. Locations with high passenger demands and low bus service frequency should be given priority. The shelter should have maximum transparency and be highly visible from the surrounding area to assure users' safety. Shelters should be of vandal proof construction and materials, durable, and easily maintained. The appearance of the shelter should be visually pleasing and in natural tones. Openings should be at least 36 inches wide. Capacity should be based on maximum passenger accumulat ion at the stop, with approximately 5 square feet per person allowed to develop size requirements. They shall not obstruct pedestrian flow or motorists' sight distance. All bus shelters shall be approved by the City Transit Manager.
1.20 STREET LIGHTING S TANDARDS
A. PURPOS E
The purpose of streetlight installations shall be to illuminate the public traveled ways to a level that provides for the safe passage of public traffic, both vehicle and pedestrian.
B. RES IDENTIAL AREAS
All lighting in residential areas shall be installed to min imize light shining on or negatively affecting the neighboring residents. Low-light trespass luminaries should be utilized whenever possible.
C. GUIDELINES
Uniform lighting will be used on new roadway projects involving Arterial and Collector streets. The guidelines shall be the Illuminating Engineering Society (IES) Lighting Handbook, latest edition, and the Design Manual of the Colorado Div ision of Highways, latest edition and supplemental revisions or guidelines approved by the City. A ll fixtures, poles, and designs will be rev iewed and approved by the power provider. Drawings for installation will be prepared by the Developer/Owner with help from the local power provider and approved by the City prior to installation. In new subdivisions, a street lighting plan will be required for approval of the subdivision. A street light will be required for all cul-de-sacs. All electrical work will be completed in accordance by NEC standards. Contractor shall install all materials in accordance with the manufacturers instructions, unless otherwise specified.
D. LAYOUT CRITERIA
1. Mounting Height Streetlight mounting height shall not exceed 20 feet in residential areas. In
areas other than residential, the mounting height shall not exceed 40 feet.
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2. Signalized Intersections Signalized intersections will be lighted using combined streetlights and
mast arms. Mounting of signals will be perpendicular to the flow line.
3. Railroad Crossing Lighting Railroad crossing lighting will conform to the Railroad-Highway Grade Crossing Handbook (FHWA).
4. Lighting in Underpasses All bridge underpasses, where vehicles, pedestrians, bicyclists, or
equestrians may be present, shall require lighting.
5. Attached Sidewalks Install street lighting behind sidewalks where sidewalks attached to the curb are used.
6. Detached Sidewalks For sidewalks detached from the curb, install street lighting with a
minimum of 2 feet clearance from back o f curb to roadway side of support pole and 2 feet clear from all walks.
7. Drawing Except within the City power service territories, drawings for installations will be
prepared by the Developer with assistance from the power p rovider and approved by the City prior to installation. In new subdivisions, a street lighting plan will be required prior to approval of the subdivision.
8. Permission for Alternate Designs Alternate designs for fixtures, if approved by the City, may be
used if installed in more than 20 locations on site. Victorian Style lighting may be required in the Central Business District and in areas of h istorical significance; such as, 8th
and 9th Avenue corridors.
9. Fire Hydrant Conflicts and Property Lines When locating proposed lighting, avoid possible conflicts with fire hydrants. Light poles shall be a minimum of ten (10') feet from fire hydrants. Light poles should be placed at property lines in residential areas where possible.
10. Roundabout Lighting Lighting columns should be arranged around the perimeter of the
roundabout in a simple ring, with the lights equidistant from the center and from each other. Lighting should extend at least 197 feet back along each approach road. Mounting height should be uniform throughout the intersection and not less than on any approach road. Minimum horizontal illuminance at the curb lines should be as given in Table 1.20-1. The minimum illuminance required should not be less than the highest level of lighting for any of the approach roads.
E. LIGHTING S YS TEMS DESCRIPTIONS
These lighting standards apply to all new street lighting systems.
F. REFRACTOR STYLE COBRA
The refractor style cobra with a Type-3 semi-cutoff distribution pattern mounted on poles shall be the standard construction for Major Collector and Arterial streets.
G. TRADITIONAL-STYLE FIXTURE
A traditional-style fixture with a Type-3 distribution mounted on steel Federal Green painted poles shall be used on local streets.
H. LIGHT TYPES AND LOCATION OF US E
Specific light types [High Pressure Sodium (HPS), Mercury, etc.] shall be installed according to City Standards. Refer to Table 1.20.2. Po les or luminaries, which are equivalent to those described below, shall be approved by the City.
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I. SPACING
The Designer shall design the spacing of all street lighting according to Table 1.20.3, and shall conform to Average Maintained Illuminance Value and Illuminance Uniform Ratio in Table 1.20.1.
J. POSITIONING AT INTERS ECTIONS
In general, the nighttime v isibility of a pedestrian or hazardous object within an intersection is enhanced by increased contrast between the object and the surrounding street area. The optimum contrast (and hence safety) is achieved when the streetlights are situated to silhouette (or backlight) objects in the intersection. Therefore, streetlights at intersections are required to be placed on the downstream side of the intersecting street, as viewed by a motorist approaching the intersection in the lane direct ly beneath the luminaries. The positioning of light standards at intersecting streets shall be as noted in Table 1.20.4.
K. PORTABLE MESSAGE S IGN PANEL
Portable message sign panel shall be furnished as a device fully self-contained on a portable trailer, capable of being licensed for normal highway travel, and shall include leveling and stabilization jacks. The panel shall display a minimum of three eight character lines. The panel shall be a dot-matrix type with an LED legend on a flat black background. LED sign shall have a pre-default message that activates before a power failure. The sign shall be capable of 360 degrees rotation and shall be able to be elevated to a height of at least five (5) feet above the ground measured at the bottom of the sign. The sign shall be visib le from one-half mile under both day and night conditions. The message shall be legible from a min imum of 750 feet. The sign shall automat ically adjust its light source to meet the legibility requirements during the hours of darkness. The sign enclosure shall be weather t ight and provide a clear polycarbonate front cover.
Each sign shall also conform to the fo llowing: 1) In addition to the onboard solar power operation with battery back-up, each sign shall be capable
of operation on a hard wire, 100-110 VAC, external power source. 2) All electrical wiring, including connectors and switch controls necessary to enable all required
sign functions, shall be provided with each sign. 3) Each sign shall be fu rnished with an operating and parts manual, wiring diagrams, and trouble-
shooting guide. 4) The portable message sign shall be capable of maintain ing all required operations under Colorado
mountain-winter weather conditions. 5) Each sign shall be fu rnished with an attached license plate and mounting bracket. 6) Each sign shall be wired with a 7-prong male electric p lug for the brake light wiring system. The portable message sign panel shall be on the project site at least seven (7) days prior to the start of active roadway construction. Maintenance, storage, operation, relocation to different sites during the project, and all repairs of the portable message sign panels shall be the responsibility of the Contractor.
L. LIGHT POLE OFFS ET DISTANCES
Distance behind back of walk for local streets shall be at least two (2') feet, and must be within easements or right-of-way on Local residential streets. For Collectors and Arterials, the light must be offset at least two (2') feet from the back of curb and provide a clearance space between the light pole and edge of walk that equals or exceeds the required sidewalk width. Pole with Break-away supports should be utilized whenever appropriate.
M. STREET LIGHTING IN MEDIANS
Street trees (full shade) shall not be placed within 40 feet of a street light. Ornamental trees shall be no closer than 15 feet to any street light.
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N. UNDERGROUND S ERVICE
Street lighting shall be installed with underground electric service on all newly developed dedicated public streets in the City. The Developer is responsible for coordinating with the appropriate utility company on all aspects of design and installation. 1 inch HDPE SDR 11 or 1 inch SCH 40 PVC conduit or approved equal shall be used for all residential roadways and 2 inch SCH 80 PVC and/or 2 inch HDPE SDR 11 is to be used along all Major Collector and Arterials, and roadway crossings for the electrical interconnect system. Conduits from the Meter and Electrical panel located by the Utility Companys approval shall be 2 inch SCH 80 PVC to the first pole location.
Substructure Conflict:
Contractor shall locate and protect substructure(s) shown on the plans and those identified by UNCC. The contractor shall provide for minimum 18 inch clearance between edge of foundation and substructures unless otherwise directed by the Inspector/Engineer. In the event an 18 inch clearance cannot be achieved, the contractor shall make arrangements for relocation of substructures at no cost to the City. Underground Service Alert:
The contractor shall obtain an underground service alert inquiry I.D. number by call 811 or v isiting www.call811.com before commencing any excavation or install ground rods. Two (2) working days shall be allowed after the I.D. number is obtained and before the excavation work is started so that utility owners can be notified. All inspections must be arranged at least two (2) days in advance. Site Preparation:
Construction in proximity of electric overhead lines: All new and existing streetlights shall conform to clearances with overhead electric power lines and communication lines. The contractor shall be responsible for all necessary coordination with responsible utility company and shall assume all costs incurred in complying with these requirements. For City of Greeley pro jects, each bidder, prio r to submitting his bid, shall inspect the job site and include in h is bid any charges by the Utility Company for de-energizing, grounding or placing effective barriers or sleeves to prevent physical contact with the lines. All costs incurred for temporary relocation of power lines shall be assumed by the City. Contractor shall not be responsible for costs incurred by the utility for any permanent relocation of lines to accommodate required clearances from street lighting equipment after construction. Underground Wire Size: Wire size to be determined by Engineer during design. Concrete Bases:
Cement bases must meet the utilitys standards and specifications for the installed light fixtu re. The bases can either be poured in place or be the prefab type.
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http://www.call811.com/
Table 1.20.1 Recommended Street Illumination Levels
(In foot-candles)
AREA CLASSIFICATION
Roadway and Walk way
Classification Commercial Intermediate Residential
Vehicular Roadways
:
Freeway Expressway
Arterial Collector
Local Alleys
0.6 1.4 1.7 1.2 0.9 0.6
0.6 1.2 1.3 0.9 0.7 0.4
0.6 1.0 0.9 0.6 0.4 0.2
Pedestrian Walk ways
Sidewalks
:
Park Walkways
0.9
0.5
0.6
0.5
0.2
0.5
Area Classification Definitions:
Commercial:
A business area of a municipality where o rdinarily there are many pedestrians during night hours. This definition applies to densely developed business areas outside, as well as within the central part of a municipality. The area contains land use which attracts a relatively heavy volume of night time vehicular and/or pedestrian traffic on a frequent basis.
Intermediate:
Those areas of a municipality often with moderately heavy night time pedestrian activity; such as, in blocks having libraries, community recreation centers, large apartment buildings, industrial buildings, or neighborhood retail stores.
Residential: A residential development or a mixture of residential and small commercial establishments, with few pedestrians at night.
Note: Values in table assume typical asphalt roadway surface (pavement classification R2 or R3). Consult the IES document for other pavement surfaces.
Source: Illuminating Engineering Society RP-8 (8).
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Table 1.20.2 Street Light Requirements
Street Classification Lighting System
Major Collector & Arterials 250-W cobra, semi-cutoff style, steel davit, 32-foot mounting height
Minor Collector & Locals 100-W Tradit ional-style, fiberg lass pole, 20-foot mounting height
Industrial/Commercial 250-W cobra, semi-cutoff style, steel davit, 32-foot mounting height
Table 1.20.3 Street Lighting Spacing
Classification Luminaries LED Spacing Layout
Major Arterial 250-W Cobra 100-W 120150 feet Staggered layout
Minor Arterial 250-W Cobra 100-W 150250 feet Staggered layout
Major Collector 250-W Cobra 100-W 150-250 feet Staggered layout
Minor Collector 100-W Pole Top 20-W 160250 feet Staggered layout
Local/Lane 100-W Pole Top 20-W 160250 feet Staggered layout
Sidewalk/Historic 70-W Pole Top 20-W 75-100 feet Entire Block
Alley 100-W Cobra 100-W 100-200 feet Entire Block
Note: Spacing to be determined by Average Maintained Illuminance Value and Illuminance Unifo rm Rat io in Table 1.20.1
Table 1.20.4 Intersection Light Locations
Major Collectors/Arterial 4 lights, one on each corner
Arterial/Arterial 4 lights, one on each corner
Collector/Collector 2 lights, one on opposite corners
Local/Collector 2 lights, one on opposite corners
Local/Local 1 light on one corner
Cul-de-sac 1 light at end of Cul-de-sac. If length>250 1 light mid-block
Alley 1 light at each end (length >400 1 light mid-block)
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1.21 SIGN STANDARDS
A. GENERAL
All signing shall be in accordance with the following design criteria and construction specifications.
B. DES IGN CRITERIA
1. All signs shall conform to current Manual on Uniform Traffic Control Devices (MUTCD),
Colorado Supplements, and the City of Greeley Standards Drawings and Specifications.
2. All signs shall be installed on Telespar type perforated posts with anchors at proper heights as per current MUTCD Standards.
3. Sign material shall be as fo llows:
a. 36" x 36" or less shall be .080 gauge aluminum pre-punched holes. b. 36" x 36" or larger shall be .100 gauge aluminum pre-punched holes. c. 36 x 8 or greater shall be .080 gauge aluminum pre-punched holes. d. All street name signs are double sided. e. Street name blanks shall be .091 gage Extruded blanks. f. The sheeting shall be High Intensity Prismat ic. g. The street sign blanks shall be a minimum 30 and a maximum of 36. The font shall be
Highway Font D. 30x30 or s maller shall be a min imum of .080 gauge aluminum 36x36 or larger shall be a min imum of .100 gauge aluminum Extruded blades shall be a min imum of .091 gauge aluminum
h. Street and Avenue signs for post mounting shall be ext ruded aluminum, 6x30 minimum to maximum of 36 in length. City of Greeley standards are reflect ive White High Intensity Prismatic background with an EC film reverse weed ing for letters, numbers, block numbers and arrows. (Highway Font D, 4 uppercase n first letter, lowercase on the rest of the name, on correct baseline, and 2 for block numbers and arrows.)
i. Stop signs must be DG3 with 3M protective coating. j. All signs shall be ordered complete with address.
4. All signs shall be 3M High Intensity Pris matic or Diamond Grade Reflective sheeting ten (10)
year guarantee, or approved equal. Legends and symbols shall be made with Electro Cut (EC) Film. The City reserves the right to request material changes to signs.
5. Sign sheeting standard, use reflective white background with green EC Film on top layer with reverse weed which shows reflect ive white blocked uppercase letters, numbers, and arrows.
6. Street and Avenue signs for post mounting shall be aluminum, 8" x 30" (minimum) in length.
7. The principal legend on guide signs shall be in letters and numerals at least 6 inches in height for
all uppercase letters, or a combination of 6 inches in height for all uppercase letters and 4.5 inches in height for lowercase letters. On low volume roads (as defined in MUTCD Section 5A.01) urban streets with speeds of 25 mph or less, the principal legend shall be in letters at least 4 inches in height for all uppercase letters, or a combination of 4 inches in height for uppercase letters and 3 inches in height for lowercase letters. Refer to Standard Details for font and height for signage examples.
8. Recommended min imum letter heights on street name signs and highway speed limit signs are as
follows:
a. Overhead all types, all speed limits (Uppercase) shall be 12 inches; (Lowercase) shall be 9 inches.
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b. Post-mounted, multi-lane, more than 40 mph (Uppercase) shall be 8 inches; (Lowercase) shall be 6 inches.
c. Post-mounted, multi-lane, 40 mph or less (Uppercase) shall be 6 inches; (Lowercase) shall be 4.5 inches.
d. Post-mounted, 2-Lane, all speed limits (Uppercase) shall be 6 inches; (Lowercase) shall be 4.5 inches.*
* If overhead street name signs are used, the lettering should be composed of initial uppercase letters at least 12 inches in height and lowercase letters at least 9 inches in height.
9. At signalized intersections these signs shall be sized in accordance with Specificat ions for
Oversize Street Signs or approved equal in Highway Standards. Use Word Font D - 12" uppercase on correct baseline.
10. All signs shall be mounted with City approved vandal type rivets and with washers.
a. 3/8" drive rivet b. 3/8" corner bolt with 5/16" nut c. Street name blade use 5/16" bolt 1/2" thread length 1/2" head d. 1 1/2" metal fender washer with 3/8" hole for signs 24" x 30" or bigger e. 1 1/4" metal fender washer with 3/8" hole for signs 12" x 24" up to 24" x24 f. 7/8" nylon washer with 3/8" hole for signs 12" x 18" or s maller
11. Telespar type posts shall meet or exceed the following:
a. Posts 2" x 2", 12 gauge, ASTM Specification No. A446, Grade A, drilled on 1" centers. b. Anchors 2 1/4" x 2 1/4" x 3', 12 gauge, ASTM Specificat ion No. A446, drilled on 1"
centers. c. All posts and anchors shall be galvanized to ASTM Specification A525 coating designation
G90.
12. Wood/Metal/Fiberglass/post mounting: Band-It Type #201 3/4" stainless steel band, Band-It Type #201 3/4" Ear-Lokt Buckle, Band-It Type #DO22 3/4" Bracket, 5/16" x 3/4" Bolt w/ six-sided head, 5/16" plastic washer.
13. Sign shall have a seven foot (7') clearance (min imum) from the bottom of sign to the ground at
installation, or as approved by the MUTCD Standards and the Public Works/Traffic Div ision.
14. All mult iple mounted signs on single post, the lowest sign shall be no lower than six (6') feet on urban roadways, with a one (1'') gap between signs. The lowest sign shall be seven (7') feet if near pedestrian or parking traffic.
15. All signs placed, with the exception of STOP and YIELD signs, shall be near property lines; they
are not to intrude on driveways, doorways, or any type of entrance.
16. For 36 o r longer street name signs, the signs shall be riveted together at ends with a 3/16 rivet.
17. Signs shall be placed behind curb to minimum specifications according to MUTCD. (Part II Signs) Standards and Colorado Supplements. City of Greeley Traffic Div ision prefers signs to be placed two (2') feet behind the curb or sidewalk whenever possible.
18. Signs shall be placed a minimum of five (5') feet from fire hydrants.
19. Placement of Stop signs shall be in accordance with City Standards. Behind curb, ramp, or
crosswalk with a minimum of 36 inches behind sidewalk at radius point or as approved by City of Greeley Traffic Div ision.
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20. Street names west of 23rd Avenue shall have a W before the street number.
21. Street names east of 1st Avenue shall have an E before the street number.
22. Avenue signs north of 1st Street shall have an N before the avenue number.
23. Arrows on street blades pointing in the direction of the 100 block shall not be placed where they would face or point across an avenue or street (they point towards the designated block).
24. Signs shall not have any company logos or decals on them.
25. Signs placed in concrete islands shall be either core drilled with a 4' hole, or a p iece of 4' PVC
pipe may be poured into the full depth of the concrete and flush with the top of concrete.
26. All sign placement shall call for current locates to the CALL BEFORE YOU DIG at 1-800-922-1987 before sign installation. Current locates shall be established before the final inspection of sign installations.
1.22 LANDSCAPE STANDARDS FOR S TREETS CAPE AND MEDIANS
The City shall approve all tree and shrub plantings on new and existing streetscapes and medians. A permit is required from the City Forestry Div ision prior to any plantings in the public right-of-way.
1.23 BIKE PATHS OR TRAIL CROSSING UNDER ROADWAYS
To accommodate both bicycle and pedestrian traffic on the existing and proposed bike path or trail system, the following shall be considered min imum clearances for bridges where the bike path or trail crossed under a roadway:
Horizontal: Twelve (12') feet from abutment to curb or edge of water. Vertical: Ten (10') feet from bike path or trail surface to underside of bridge. Note: The bike path of trail surface elevation should be at or above the high water
mark for the two (2) year storm. 1.24 DECELERATION LANES AND TURNING LANES
A. GENERAL
A traffic impact study, along with the City Engineer, shall determine the need of decelerat ion lanes and turning lanes.
B. DES IGN CRITERIA
1. The required decelerat ion lengths excluding stored vehicles are based on the design speed for the
Arterial and are as follows:
Design Speed (mph) 30 40 45 50 55 Decel. Length (ft) 230 330 430 550 680
2. These lengths include the taper length. On many Arterials, it is not possible to provide the full deceleration length due to existing conditions. In such instances, it will be necessary to coordinate the design with the City Engineer.
3. On deceleration lanes where it is necessary to store stopped vehicles (such as at traffic signals),
additional lengths shall be provided to accommodate the average number o f vehicles anticipated at the peak hour, per signal cycle, if indicated from the most recent traffic impact analysis. In such
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cases, the storage length shall be added to the deceleration length to arrive at the total length. The recommended storage length for non-signalized intersections is as follows:
Turning vehicles per hour 30 60 100 200 300 Storage Length (ft) 25 50 100 175 250
1.25 STREET MARKINGS STANDARDS
A. GENERAL
All street markings shall be in compliance with the current Manual of Uniformed Traffic Control Devices Standards and the following design criteria.
B. DES IGN CRITERIA
1. Refer to Construction Specifications Section 02618 of this manual for information on materials
and construction.
2. The Design Engineer may use the current version of the CDOT M&S Standards, Standard Plan No. S-627-1 Typical Pavement Markings for guidance when preparing roadway plans.
1.26 TRAFFIC SIGNAL STANDARDS
A. GENERAL
All t raffic signals shall be incompliance with the current Manual of Uniformed Traffic Control Devices Standards and the following design criteria.
B. DES IGN CRITERIA
1. The Traffic Division maintains current standard drawings and construction specifications for
traffic signals which can be fu rnished to the Design Engineer upon request. Before materials are ordered, contact City of Greeley Traffic Div ision.
2. In general, the Design Engineer can use the current version of the CDOT Standard Specifications
for Road and Bridge Construction, Section 614 Traffic Control Devices for guidance when preparing roadway plans.
1.27 TRANSPORTATION IMPACT STUDY (TIS)
A. INTRODUCTION
1. General This document contains the policies and guidelines necessary for the preparation of Transportation Impact Studies (TIS) for development proposals for the City of Greeley. The policies exist to ensure consistent and proper traffic p lanning and engineering practices when land use actions are being considered with in the City of Greeley. The guidelines provide for a standard process, set of assumptions, set of analytic techniques, and presentation format to be used in the preparation of the TIS.
2. Applicant Responsibility The responsibility fo r assessing the transportation impacts associated with an application for development approval rests with the Applicant. The City serves in a review capacity. The assessment of these impacts shall be contained within a TIS report as specified herein. It shall be prepared under the supervision of, and sealed by, a Licensed Professional Engineer in the State of Colorado with experience in traffic engineering and transportation planning/engineering. For all State Highways
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within the study area, the Applicant is required to meet the requirements of the Colorado Department of Transportation.
3. Capacity and Safety Issues Development of property has a direct impact on transportation, including vehicular, transit, b icycle, and pedestrian traffic. In o rder to meet capacity and safety needs as they relate to the traffic generated from a particular land use, specific improvements can be made. The goal of the TIS is to address the traffic related issues that result from the new development and to determine the improvements required such that appropriate levels of service are safely maintained. The competing objectives of vehicular movement, pedestrians, bicyclists, and others must be balanced in the development review process. A balanced combination of elements is needed to provide streets that serve all transportation modes. The TIS will p rovide information and guidance as plans are developed and decisions made for the approved plan.
a. Vehicular Traffic Improvements. Examples of capacity and safety improvements for vehicular traffic include: road widening, turn lanes, acceleration and decelerat ion lanes, intersection through lanes, traffic signals, modern roundabouts, stop signs, design speed adjustments, and modifications to access points.
b. Pedestrian Traffic Considerations and Improvements. Examples of safe, comfortable, and convenient pedestrian services are narrower roadways with fewer lanes, short blocks, low traffic speeds, tree-lined sidewalks, smaller corner radii, well-defined crosswalks, median refuges and channelized islands in large street crossings, on-street parking, and bicycle lanes. Walkway tunnels or overhead structures are examples of safety improvements where vehicular traffic causes unsafe conditions for pedestrians, and where space is available for the needed ramps or steps.
c. Bicycle Traffic Improvements. The addition of on-street bicycle lanes or off-street bicycle paths may be needed to achieve connectivity between the proposed project and the existing bikeway system.
d. Transit Traffic Improvements. Examples of Transit Traffic Improvements include accommodation of public transit facilities such as buses, bus stops, bus bays, stations, and transit stop facilit ies.
B. REQUIREMENTS AND CRITERIA
1. Scoping Meeting a. Purpose
The purpose of the scoping meeting is to determine the parameters for the study of traffic impacts for a specific development pro ject, and to document those parameters. The parameters determined in the scoping meeting represent general agreement between the City and the consulting engineer, but they may not be all- inclusive. The City retains the right to require any additional information and / or analysis to complete an evaluation of the proposed development project. Attachment A is completed at this meeting and is included in the submitted Transportation Impact Study.
b. Meeting Setup and Content The Applicant is required to contact the City to arrange for a Scoping Meeting to discuss the TIS requirements and determine the base assumptions. It is incumbent upon the Applicant to bring a completed or partially completed Transportation Impact Study Base Assumptions Form and be prepared to discuss the following:
1. Previous TIS prepared for the site, if any; 2. Location of the site; 3. Proposed access and its relationship to adjacent properties and their existing/proposed
access;
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4. Preliminary estimates of the site's trip generation and trip distribution at build-out; 5. Identification of proposed year of build-out; 6. Trip adjustment factors proposed, if any; 7. Approved and proposed developments in the study area, and the associated committed
roadway improvements; 8. Anticipated roadway improvements to be provided by the Applicant; 9. Phasing plan proposed; 10. Potential b icycle and pedestrian connections to the nearest attraction (existing or
imminent) with in 1320 of the site. This distance may be increased up to 1.5 miles for residential projects near existing or proposed school sites.
c. If a scoping meeting was conducted six months prior to the submittal of the TIS, the City reserves the right to require another scoping meeting.
2. Types of Study a. Master TIS
Where large complex pro jects are planned or a project is phased over a multi-year build-out, it may be appropriate to prepare a Master TIS for the initial land use action followed by periodic updates for specific phases. The Master TIS must include overall phasing of improvements to coincide with project phasing. Updates to the Master TIS shall be submitted with the land use applications for the specific phases, and shall meet the requirements for the Indiv idual Site Transportation Impact Study. This type of study may also be required for annexations and zoning applicat ions for large tracts of land.
b. Individual Site Trans portation Impact Study An individual site TIS is prepared for a project that stands alone or is a phase of a master development. It can be for a new use in an existing or remodeled building, the construction of a new building (either single occupant or multi-user), construction of mult iple buildings, or the construction of new residential development.
3. Levels of Analysis
For an Individual Site Transportation Impact Study, the following levels of analysis apply: (These categories are intended as guidelines and may be revised, when warranted, by the City Traffic Engineer:
a. Full TIS A Full TIS shall be required if one or more of the fo llowing conditions occur:
1. Vehicu lar Traffic a. The site generated traffic exceeds 1,000 trips/day and/or 100 peak hour trips, or b. New high volume access is requested for an arterial street or State Highway.
2. Pedestrian Traffic Paved pedestrian facilit ies exist or will be constructed on, or adjacent to, the site; or, the proposed use will generate significant pedestrian traffic.
3. Bicycle Traffic Paved bike lanes or paths exist or will be constructed on, or adjacent to, the site; or, the proposed use will generate any new bicycle traffic.
b. Intermediate TIS An Intermediate TIS may be considered if all of the following requirements are met :
1. Vehicu lar Traffic a. Daily vehicle t rip-end generation is between 501 and 1000 inclusive, or the peak hour trip generation is between 51 and 100, and
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b. No high volume access onto Arterials or State Highways are being requested, and c. The Level of Service (LOS) of the adjacent facility when the development is completed equals or exceeds the minimum allowable LOS standard established for that facility.
2. Pedestrian Traffic Paved pedestrian facilit ies exist or will be constructed on, or adjacent to, the site; or, the proposed use will not generate any new pedestrian traffic.
3. Bicycle Traffic Paved bike lanes or paths exist or will be constructed on, or adjacent to, the site; or, the proposed use will not generate any new bicycle traffic.
c. Transportation Memorandum A Traffic Memorandum, in lieu of a more detailed study, may be considered if all the following requirements are met :
1. Vehicu lar Traffic a. Daily vehicle t rip-end generation is less than or equal to 500, and/or the peak hour trip generation is between 21 and 5 and, b. Any new access requests are for local streets or minor co llector streets only.
2. Pedestrian Traffic Paved pedestrian facilit ies exist or will be constructed on, or adjacent to, the site; or, the proposed use will not generate any new pedestrian traffic.
3. Bicycle Traffic Paved bike lanes or paths exist or will be constructed on, or adjacent to, the site; or, the proposed use will not generate any new bicycle traffic.
d. No TIS Required The TIS requirement may be waived if all o f the criteria below are satisfied:
1. Vehicu lar Traffic a. Daily vehicle t rip-end generation is less than 200 and/or the peak hour trip generation is less than 20 b. There are no additional proposed minor or major street intersections on major collectors, arterials, or State Highways; c. If the property is being redeveloped, the increase in the number of vehicular trips for the proposed use does not exceed the trip generation from the existing use by more than 20 peak hour trips or 200 daily trip ends; d. Any change in the type of traffic to be generated (i.e. the addition of new truck traffic) does not adversely affect the traffic currently planned for and accommodated within, and adjacent to, the property; e. The scale or use of the proposed development or redevelopment is not likely to cause less than acceptable levels of service on the adjacent public streets, accesses, and intersections; and f. The proposed development or redevelopment is not in the vicinity of a street or intersection with a history of safety and/or accident problems. g. There is no change of land use with access on to a State Highway.
2. Pedestrian Traffic Paved pedestrian facilit ies exist or will be constructed on, or adjacent to, the site; or, the proposed use will not generate any new pedestrian traffic.
3. Bicycle Traffic Paved bike lanes or paths exist or will be constructed on, or adjacent to, the site; or, the proposed use will not generate any new bicycle traffic.
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4. Revisions and Updates A revision or update to an approved TIS may be required when a previously approved land use action proposes an expansion, a change to access, or a change in use where new trip generation estimates exceed the original trip-end generation estimates. If the currently approved study was prepared within the last three years, an amendment letter addressing the changes may be accepted and satisfy the requirements of this guideline. If an existing TIS is more than three years old, a new TIS is likely to be required.
C. STUDY PARAMETERS 1. Project Description
A description of the proposed project will be prepared and include the type of land use and size of the proposed project (number of dwelling units or building square footage). Any proposed phasing will be discussed and the anticipated completion date established. A figure depicting the proposed site plan will also be included and the proposed vehicular access locations will be described. This section will also include a description of how pedestrian and bicycle travel will be accommodated within the proposed site plan. This will include a discussion of types of sidewalks (attached/detached), pathways, and connections to local and perimeter destinations.
2. Analysis Horizons Three study horizons a